STM32F4 - MCO1 gives SYSCLK when asked for PLLCLK

[fufu930]

On STM32F4, when you choose PLLCLK as the MCO1 source, does the HAL actually routes the PLL output going into SYSCLK, i.e. after the PLLP division?

#include <Arduino.h>
#include <RCC.h>

void SystemClock_Config(void)
{
 RCC_OscInitTypeDef RCC_OscInitStruct = {0};
 RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

 __HAL_RCC_PWR_CLK_ENABLE();

 RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
 RCC_OscInitStruct.HSEState = RCC_HSE_ON;
 RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
 RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
 RCC_OscInitStruct.PLL.PLLM = 25;
 RCC_OscInitStruct.PLL.PLLN = 336;
 RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV4;
 RCC_OscInitStruct.PLL.PLLQ = 7;

 if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
 Error_Handler();
 }

 RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_SYSCLK |
 RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2;
 RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
 RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
 RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
 RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

 if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK) {
 Error_Handler();
 }
}

void SystemClock_Test_1(void)
{
 __HAL_RCC_GPIOA_CLK_ENABLE();

 GPIO_InitTypeDef GPIO_InitStruct = {0};
 GPIO_InitStruct.Pin = GPIO_PIN_8;
 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
 GPIO_InitStruct.Alternate = GPIO_AF0_MCO;
 HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

 HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_PLLCLK, RCC_MCODIV_1);
}

[TDK]

Per the reference manual, yes. It outputs PLLP. This may or may not be SYSCLK, depending on the system clock mux.